Need advice on this princess cut, please!

[bdavis48]

Engagement time is closing in on me! After 8 billion hours searching around for a nice princess cut stone, I''ve found:

1.01 carat
GIA
D
VS1
Depth 68
Table 68
G: Thin to Medium, Faceted
5.66 x 5.65 x 3.84
P: VG
S: EX
F: none

Sarin info:
Table: 3.87, 3.84, 3.89, 68.6
Crown Angle: 34.9, 34.4, 36.0
Crown Height: 0.46, 0.46, 0.46, 8.2%
Pavil Angle: 61.8, 60.0, 63.0
Pail Depth: 3.20, 3.20, 3.20, 56.7%
Girdle: 1.4%
Total Depth: 3.83, 67.9%

OK, first, I''m not sure why the Sarin report shows three sets of measurement for crown angle, height, and pavil. angle, depth. Why is that? After hours of searching, I cannot find any guidelines for crown angle, pavilion angle and pavilion depth for princess stones.

Second, can I get your opinions as to the overall quality of the stone? Do you see any show-stoppers? It fits right into the 1A category (except for crown height). Any guesstimates about the "fair" market value for such a stone?

I would like to send it to consumers gem labs for a second opinion as well, since the stone is out of town and I cannot see it personally.

Thank you!

 

[researcher]

I'm no expert, but my understanding is there are 2-3 different angles for the crown etc. which is why you have a few numbers listed for each.

As far as the numbers go, the stone looks good except for the crown--which you noted. This would, I believe, impact the fire of the stone.

Do you have an ideal scope image or pic of the stone itself?

 

[bdavis48]

The crown height is a little low, but not too far off the mark? And it seems like there should be four measurements for crown angles, etc., on a square stone. But perhaps three is enough to determine the fourth?

 

[researcher]

I have no clue. All I know is there are something like 50 or 58 facets, and sarin reports measure certain angles in relation to these.

For 50 facets: 21 crown, 4 girdle, 25 pavilion facets
For 58 facets: 21 crown, 4 girdle, 33 pavilion facets

I'm not sure, but I would guess you get a measure for the two crown breaks (girdle and table) and...who knows?

I'm not going to pretend to know what I'm talking about. All I'm sure of is when I try to apply common sense (and trig formulas) to diamonds it never seems to work.

Hopefully someone who actually knows something will respond!!!

 

[bdavis48]

A picture of the diamond is attached, and I have asked for an ImageScpoe photo. Any thoughts? What is going on in the red circled area? It looks like clearly visible inclusions, but it's a VS1 and the GIA report does not show inclusions in that locaiton.

 

[bdavis48]

Sorry, the wrong image got attached...here is the red circled area...

 

[researcher]

It looks like it might just be a reflection, or at worst a place with a little light leakage or a facet that is cut a little off. If the plot doesn't show anything there, you probably don't have anything to worry about!

 

[moremoremore]

Listen to EVERYTHING researcher tells you!

and p.s.- love the stone!

 

[researcher]

I don't know about that; have you seen some of my earliest posts? Actually, did you see the post in which I tried to explain the various angles measured on the crown? Horrible! I had no idea what I was talking about! I guess I should stick to telling people how to run their companies, not how to buy diamonds....

 

[valeria101]

In the red circle... on the larger white facet... there is a little spot - probably the main inclusion of the stone. It took a second look.

There is no interpretation of angles for a princess cut around here, but Jonathan was working on such a thing. No HCA for princess cuts though and no sure-fire receipe. All those numbers coudl probably generate a reasonable model of the stone (GemAdviser and DiamCalc come to mind) but none would be as true to nature as a direct observation of ligth return. Hope to see that 'scope picture soon

 

[valeria101]

----------------
On 6/2/2004 8:29:37 PM bdavis48 wrote:



And it seems like there should be four measurements for crown angles, etc., on a square stone. But perhaps three is enough to determine the fourth?

----------------

You may want to look down THIS LINK for a MegaSCope report with the respective angles placed on the right pieces of the cut diagram...

 

[valeria101]

----------------
On 6/3/2004 3:56:40 PM researcher wrote:



I guess I should stick to telling people how to run their companies, not how to buy diamonds....
----------------

C'mon... No way

Forget the gem-cutting encyclopedia - it's not a thick volume at all. Wisedom is great in any form of aggregation, public or private

 

[bdavis48]

Thank you for all of the replies so far.

Is anyone troubled by the fact that the total sarin depth (67.9%) is greater than the sum of the crown (8.2), girdle (1.4) and pavilion (56.7) = 66.3%?

 

[valeria101]

----------------
On 6/3/2004 7:22:07 PM bdavis48 wrote:

Thank you for all of the replies so far.

Is anyone troubled by the fact that the total sarin depth (67.9%) is greater than the sum of the crown (8.2), girdle (1.4) and pavilion (56.7) = 66.3%?----------------

Not me.

Those are averages of eight imprecise measurements AND the girdle outline varies by design. Besides, not all those are actual measurements, besides being averaged out, some of those are obtained by calculation (Sarin would measure angles, as far as I know, and the rest gets deduced from there, other intruments- no idea.) I would definitely not expect any better accuracy.

Those shoud add up at each measurement point, not on average - and then, assuming measurements for crown, pavilion and depth were done at the same point around the stone.

If the girdle measurement would have read "thin to extra thick" or ssuch ont he cert, one may ask what's all that variation about, but with "thin to medium" - no red light at all.

 

[valeria101]

... this is where the numbers on the cert comes from... any wander they do not add up straight

?